If looks like you have no idea how delegates work, not mentioning events and their relationship. It's hard to explain all in once, while C# and .NET manuals provides detailed explanation.
First, read this:
http://en.wikipedia.org/wiki/Delegation_%28programming%29[
^].
Start here:
http://msdn.microsoft.com/en-us/library/ms173171%28v=VS.100%29.aspx[
^]. Learn
all about delegates and move here:
http://msdn.microsoft.com/en-us/library/awbftdfh.aspx[
^]. Try to understand their relationships.
In a nutshell, delegates and events are all about
inversion of control, see
http://en.wikipedia.org/wiki/Inversion_of_control[
^]. The method of abstraction achieved with delegates is simply impossible with methods. A delegate is a .NET way of operating "methods" (in a generalized sense of this words) as
first-class citizen object, see
http://en.wikipedia.org/wiki/Functional_programming[
^],
http://en.wikipedia.org/wiki/First-class_function[
^],
http://en.wikipedia.org/wiki/Higher-order_function[
^]. Simply put, a method can not be assigned to a variable (a method itself, not its return value or something), but a delegate instance can be.
A delegate instance object is a complex object of some class (and this is not of the type of the corresponding delegate type), which carries an invocation list, which is a list of handlers each carrying a pointer to a code of a method and a reference to an object on which an instance method is called — "this" reference (it could be null which means the method is static). You can store the delegate instance in some variable and pass it to some method, or assign it to some type (class or structure) field or property.
Please see my article "
Dynamic Method Dispatcher" where I explain it in further detail in the section "4.1 On the Nature of Delegate Instance".
Note: such explanation is hard to find, so please read mine.
When you develop some class, you don't want to limit all calls with the methods of this class, and not even with the method of the class hierarchy like you would do using virtual methods. You want to say: "when something happen, I want to call some method which a user wants to supply". This is how inversion of control works here. Are you getting the picture? For further detail, read the manuals.
—SA
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